Virulence Evolution in Multi-pathogen Systems

Most infections are made up of more than one parasite strain, and many of those multi-strain infections exist alongside additional parasite species.  I’m interested in understanding how interactions between parasite species at both within- and between-host scales impact the evolutionary trajectory of important parasite traits like virulence and infectivity.  I use the host Daphnia dentifera and two of its common parasites, the fungus Metschnikowia bicuspidata and the bacterium Pasteuria ramosa, as a study system.

I’m currently testing within-host interaction effects on parasite fitness and host mortality rate, and have had help in the past from undergraduate Julie Meng.  This work will provide insights into the ways coinfections with different parasite species—a common occurrence in nature—can influence parasite virulence.  This will also serve as a springboard for future projects on coinfection dynamics.